Stents and stent delivery assemblies are utilized in a number of medical procedures and situations, and as such their structure and function are well known. A stent is a generally cylindrical prosthesis that is introduced via a catheter into a lumen of a body cavity or vessel. The stent is introduced into the cavity or vessel with a generally reduced diameter and then is expanded to the diameter of the cavity or vessel. In its expanded configuration, the stent supports and reinforces the cavity/vessel walls while maintaining the cavity/vessel in an open, unobstructed condition.
Typically, when deploying an endoscopically delivered stent in a body cavity of interest, a guidewire is introduced into the body cavity through a working lumen defined in an endoscope to ensure proper placement of the prosthesis. The guidewire is used to ensure that the device is properly positioned and the deployment device is maintained in the proper position during deployment of the prosthesis. A physician advances an endoscope to identify the stricture location by observing an image received from the distal end of the endoscope. A dilation device is advanced through the scope and the dilation device is used to dilate the stricture. Once the position of interest, as observed by the endoscope, is identified, internal and/or external markers are placed to identify and indicate the stricture location. The endoscope and the dilation device are then withdrawn. Thereafter, a stent delivery catheter is advanced to the stricture location, using fluoroscopy (x-ray imaging of a moving object), and the deploy stent. To observe and ensure proper deployment of the stent, the endoscope is re-introduced to confirm stent placement. In addition, fluoroscopy is often used to ensure proper placement and deployment of the stent, as well known in the art.
The use of an endoscope in combination with a dilation device, however, requires additional steps to locate the stricture, introduce a dilation device, and placing markers. Still further, use of fluoroscopy to confirm proper positioning of a stent is a relatively cumbersome procedure and requires additional safety mechanisms for the patients as well as the doctors and their assistants.
A need exists for a vision system that is integral with the stent delivery and dilation system to provide a device that deploys, dilates and provides imaging in a single device. A need exists for a single device that provides visualization, dilation and deployment of a prosthesis without the required use of fluoroscopy and/or a separate endoscope.